The demonstrated utility and economic viability of microsystems technology in applications where silicon-based electronics are well suited to the environmental conditions, such as consumer electronics, healthcare, and telecommunications, has stimulated demand for comparable systems for environmentally demanding applications. Implementations of microsystems in these areas are envisioned to improve efficiency and extend operational lifetime of key components by enabling closed-loop control through the integration with control electronics. However, the harsh operating environments in high temperature and/or vibration environments, such as gas turbine engines, oil and gas drilling equipment, and vehicle engines and exhaust, significantly impede the ability to accurately diagnose potential problems.
Currently, these systems lack the type of on-board control that is possible using microsystems technology due to the extreme operating conditions of system. In situations where sensor-based technologies have been implemented, the sensing part of the system is often offset from the position of interest due to inherent temperature limitations of the electronics, peripheral passive components (capacitors, inductors), and often the sensing elements themselves. Advancements in packaging technologies have not been sufficient to overcome the temperature limitations while maintaining miniaturization, which are ultimately bounded by the temperature stability of the silicon-based electronics.
Approaches to locate the temperature-sensitive electronic components to cooler sections of the system have been implemented, but these approaches result in a much larger system that has significantly more wiring, larger packaging, and degradation of the transduced signal due to the displacement of the signal conditioning electronics from the sensor. Next generation maintenance and monitoring systems are envisioned to adopt an integrated approach, which requires distributed control systems using smart sensing technologies. Smart sensing technologies that could monitor pressure, temperature, vibration, and emissions may significantly improve engine performance and service lifetime. However, such smart sensing systems require deployment in some of the most aggressive environments of an engine in order to provide more accurate in-situ dynamic data acquisition. Conventional systems are ill-suited for such deployment. Accordingly, an improved sensor system may be beneficial.